I'm pretty sure this has been but I haven't been able to find it in the Forum.
89 iroc, 5.7 tpi. I had to change the fuel pump so I went ahead and went the route of lifting up the back and taking the tank out, with a helper. Before I could get to the garage he had unhooked the lines and removed straps. Break for vacation travel occurred, and I for the life of me I cannot remember which line hooked where to the lines running up to the motor.
sending unit has 4 lines an only the 3 going to the motor. I know which one the supply is but what is the deal with the extra one? I've tried and tried to remember what it looked like sitting in there before it was unhooked if anybody could help me label these I would greatly appreciate it.

 

One is to the tank vent (UFO looking thing)

 

Thanks man. I was wondering what that was for
Appreciate the help

 

You should have 4 lines. The feed is the one that has threaded fittings. Then you have the return line, a vent line to the charcoal can, and then the relief valve.